Direct-current relay



March 1, 1932. L, g FREEMAN 1,847,339

DIRECT CURRENT RELAY Filed July 10. 1931 INVENTOR. A. C, Fkaaman,

/ '4! ATTORNEYQ Patented Mar. 1, 1932 UNITED STATES PATENT (ii-"Flor.

LEWIS C. FREEMAN, F SWISSVALE, PENNSYLVANIA, ASSIGNOB TO THE UNION SWITCH A: SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A CORPOBATION O1 PENN- SYLVANIA.

DIRECT-CURRENT RELAY Application filed July 10,

My invention relates to direct current relays, and particularly to relays of the type comprising a neutral armature responsive to the presence and'absence of current and a 6 polarized armature responsive to the polarity of the current supplied to the relay.

One feature of my invention is the provision of a novel and improved relay of this character which is so designed that the neu- 1 tral armature will not release when the polarity of the current supplied to the relay is reversed. I

I will describe one form of relay embodying my invention, and will then point out the novel features thereof in claims.

In the accompanying drawings, Fig. 1 is a view showing in front elevation one form of relay embodying my invention. F i 2 is a top plan view of the relay shown in ig.

1. Fig. 3 is a bottom plan view of the relay shown in Fig. 1 with the armatures removed. Fig. 4 is a bottom plan view of the neutral armature D forming part of the relay shown in the preceding views.

Similar reference characters refer to similar parts in each of the views.

Referring to the drawings, the relay comprises two complete electromagnets A and B havin a common backstrap 4. Magnet A is made up of two parallel coresland 2*, while magnet B is made up of two similar parallel cores 1 and 2 These cores are all attached at their upper ends to the backstrap 4, and at their lower ends they pass through the usual top plate 5 of insulating material. The cores of magnet A terminate' beneath the top plate 5 in pole pieces 11 and 12, while the cores of magnet B terminate beneath the top late in similar ole pieces 11 and 12 agnet A is provlded with a winding 6 located on the core 1*, and magnet B is provided with a winding 6 located on the core 1 Magnet A is of the ordinary quick-releasing type, whereas ma et B is made slow-releasing in character y suitable means, such, for example, as a copper sleeve 3 on the core 1 I Co-operating with the magnets A and B is a. neutral armature D comprising two spaced magnetizable members 9 and 9 conmi. Serial no. 548,878.

nected by non-magnetizable members 10.

The armature D is pivotally mounted in the usual trunnions 11 and 12, which are supported in brackets 7 and 8 projecting downwardly from the top plate 5. The parts are so arranged that the armature member 9 co-operates with the pole pieces of magnet A, and the armature'9 co-operates with the pole pieces of magnet b.

The relay also comprises a permanent magnet C, WhlCll is parallel with the cores of magnets A and B, and is located between these magnets but is offset from the line connecting them, as shown in Figs. 2 and 3. The

upper end of magnet C is attached to the backstrap 4, and the lower end passes through the top plate 5 and terminates in a pole piece 14. The underside of the pole piece 14 is slotted to receive a polar armature F which is pivotally mounted at its middle point in trunnions 15 carried by the pole piece 14. The two ends of the polar armature F co-act with extensions 13 and 13 on the pole pieces 11 and 11 respectivel The windings of magnets A and are included in a circuit which is connected with a source of current, the terminals of which are designated X and Y in Fig. 1. This circuit includes a pole-changing switch E, whereby current of one polarity or the other may be supplied to both magnets.

The parts are so arranged that when the pole-changing switch E is in the position shown in Fig. 1, the fluxes in the magnetic circuits of the two magnets A and B are in the directions indicated by the arrows. That is to say, pole pieces 12 and 11 are north, while pole pieces 11 and 12 are south. The permanent magnet C is so mounted that its pole piece 14 is south, and, consequently, under the conditions illustrated in Fig. 1, polar armature F is swung in clockwise direction, so that its left-hand end is in contact with extension 13 on pole piece 11-. I will now assume that pole-changer E is reversed, thereby reversing the direction of the flow of cur-' rent in the magnet windings (S and 6. When this reversal occurs, the direction of the flux in magnet A and armature member 9* will reverse at once, whereas the reversal of the will be delayed due to the copper sleeve 3 on core 1 It follows that while the flux in armature member 9 is passing through zero, the flux in armature 9 will still be of considerable value, so that the zero condition of the flux in magnet A will not permit armature D to release. Subsequently, after the flux in magnet A has built up to a considerable value in the reverse direction, the flux in magnet B will pass through zero, but the armature D will still not release because the flux in its member 9 will then be of considerable value. Finally the flux in magnet B will build up to its normal value in the reverse direction, so that armature D will be held in its closed position by both magnets. It follows that armature D will not release during the reversal of the direction of current in the windings of magnets A and h The reversal of the polarity of magnets A and B will result in pole piece 11 and extension 13 becoming south, and pole piece 11 and extension 18 becoming north, and this will, of course, cause polar armature F to swing in counter-clockwise direction to its reverse position.

Although I have herein shown and described only one form of relay embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. A relay comprising two spaced electromagnets one of which 1s slow-releasing and the other of which is quick-releasing, means for supplying both of said magnets with direct current of one polarity or the other, a neutral armature having two magnetizable members spaced by a non-magnetizable memher and co-operating with said two magnets respectively, and a polarized armature coacting with said two magnets.

2. A relay comprising two spaced electromagnets made up of four parallel cores connected by a common backstrap, one of which magnets is slow-releasing and the other of which is quicloreleasing, means for supplying both of said magnets with direct current of one polarity or the other, aneutral arma ture' having two magnetizable members spaced by a member of non-magnetizable material and co-operating with the free ends of the cores of said two magnets respectively, and a olarized armature co-acting with one pole 0 one said magnet and the unlike pole of the other.

' 3. A relay comprising two spaced electromagnets made up of four parallel cores connected by a common backstrap, one of Which magnets is slow-releasing and the other of both of said magnets with direct current of one polarity or the other, a neutral armature co-operating with the free ends of said two magnets, and a polarized armature co-acting with said two magnets.

4. A relay comprising two s aced electromagnets made up of four para lel cores connected by a common backstrap, one of which magnets is slow-releasing and the other of which is quick-releasing, means for supplying both of said magnets with direct current of one polarity or the other, a neutral armature co-operating with the free ends of said ,two magnets, a permanent magnet connected with said backstrap, and a polarized armature pivotally attached to the free end of said permanent magnet and co-acting with one pole of one electromagnet and the unlike pole of the other.

5. A relay comprising two spaced electromagnets made up of four parallel cores connected by a common backstrap, one of which magnets is slow-releasing and the other of which is quick-releasing, means for supplying both of said magnets with direct current of one polarity or the other, a neutral arma' ture having two magnetizable members spaced by a member of non-magnetizable material and cooperating with the free ends of the cores of said two magnets respectively, and a polarized armature pivotally attached to the free end of said permanent magnet and co-acting with one pole of one electromagnet and the unlike pole of the other.

In testimony whereof I aliix my si ature.

LEWIS 0. FREE AN.

which is quick-releasing, means for supplying 

